Multilayer Antenna Research Articles

Analytical design of low-profile wideband multi-layer transmitarray antenna for Ku band

Analytical design of low-profile wideband multi-layer transmitarray antenna for Ku band

Multilayer multiband hybrid fractal antenna for public safety and 5G Sub-6 GHz bands

In this work, a multiband hybrid fractal antenna is developed for public safety and 5G Sub-6 GHz bands. Proposed antenna design is designed, analyzed, and optimized using HFSS simulator. Radiating element of the proposed antenna consists of Hybrid Fractal shape which is designed using Koch and Hilbert curve fractal geometry. Hybrid Fractal Antenna (HFA) is designed on a Multilayer FR4 substrate which has an overall size of 0.22 × 0.47 × 0.044 ƛ3. Parametric analysis of the proposed design is done to get the optimum results. Proposed HFA resonates at 2.64 GHz (2.34–2.80 GHz), 3.87, 4.54, 5.02, 5.35 GHz (3.73–5.55 GHz), and 6.42 GHz (5.70–6.72 GHz) with a gain of 4.2, 0.9, 2.9, 3.3, 4.6, and 3.7 dBi respectively. The proposed HFA is useful for 5G bands such as: N7 band, N38 band, N40 band, N41 band, N47 band, N53 band, N79 band, N90 band and N93 band, and also useful for public safety band (4.9 GHz). Prototype of the proposed HFA is fabricated and tested in lab for the verification of simulated results. The results show good performance in terms of reflection coefficient, gain, and bandwidth. Measured results are in good agreement with the simulated results.

The Design and Implementation of a Wide-band Circularly Polarized Conformal Antenna

Background: It gives out the design and verification of single-layer dual-band antenna unit and multi-layer dual-band broadband antenna unit of phased array antenna, and verifies that the multi-layer dual-band broadband antenna unit can meet the design requirements of the receiving frequency band. Objective: It gives out the design and implementation of a wide-band circularly polarized conformal antenna, and presents the characteristics analysis of the antenna. Method: Through related simulation methods, the proposed methods are verified and they can effectively solve the array phase compensation and beam shaping and control in the wide-band circularly polarized conformal antenna. Results: Based on the basic design of the antenna, the active superposition algorithm, phase compensation technology and particle swarm optimization antenna beam shaping technology are both studied. Conclusion: The proposed wide-band circularly polarized conformal antenna can be used in the actual application.

Multi-layer meta-surface low-profile antenna using artificial intelligence for 5G and optical communications

Multi-layer meta-surface low-profile antenna using artificial intelligence for 5G and optical communications

Transparent dielectric/metal/dielectric multilayer microstrip patch antennas for X and Ku-band

Optically transparent antennas are in high demand due to their critical role in healthcare, automotive and industrial sectors. These antennas face challenges in adjusting thickness for high optical transparency and also high conductivity for enhanced antenna characteristics. We mitigate the trade-off between optical transparency and antenna performance by pioneering the introduction of multiple sandwich structures in optically transparent antennas, for the first time in the literature, to the best of our knowledge. Three transparent multilayer antenna structures are designed as a rectangular patch antenna and fabricated on polycarbonate substrates. The multilayer structure consists of Ag layers sandwiched between layers of TiOx, SixNy, and ZnAlOx. Fabrication of the multilayer structures are verified by scanning electron microscopy (SEM). Optical transparencies of 85%, 73%, and 68% are achieved at a wavelength of 550 nm for one, two, and three layers of Ag, respectively. Scattering parameters and radiation patterns of the antennas are measured and simulated. For the antenna including triple dielectric/Ag/dielectric sandwich structure; peak gain, directivity and efficiency are obtained as 3.013 dBi, 8.072 dBi, and 37.5%, respectively. The agreement between measurements and simulations, together with the antenna performances obtained, validates our novel transparent antenna design.

A MIMO-Based Dual Polarized Antenna Applicable for Mobile Terminal

At present, numerous small-size mobile terminal devices, such as mobile phones, have embedded the antenna in the cases, which will lead to considerable restrictions on the space for installing multiple antennas. Aiming at the requirements of rational design and layout of multi-antennas for MIMO mobile terminals and combining with the broadband and miniaturization technologies, a dual polarized antenna suitable for mobile terminals was designed in this paper through an adoption of polarization diversity. For a dual polarized multilayered micro-strip antenna with a ground plate, it is easy to be conformal to the carrier. In this paper, the design and the process of simulation optimization of the antenna unit were analyzed in detail. The bandwidth of the antenna unit was 1890 to 2200 MHz, the return loss was superior to -33dB, and both of the horizontal polarization gain and the vertical polarization gain were 8.2 dB. Accordingly, the characteristics of a high gain and dual polarization were achieved.

Horn Antenna on Chip Operating at 180 GHz Using the SiGe CMOS Process

This article proposes a chip antenna on millimeter-Waves. This antenna combined with TSMC 180 nm SiGe CMOS technology has the advantage of being small in size and is suitable for wireless communications. The multilayer architecture Horn antenna implemented on M4–M6 can meet both process reliability specifications and radiation performance. The results of the simulation show that the maximum gain is −4.2 dBi. The return loss measurement results are almost consistent with the simulation results, and the bandwidth range is 177.4–183 GHz. This article first describes the antenna production process and measurement results, analyses the impact of the parameters on the antenna, and further compares it with other designs. The excellence of this article is that it proposes a design that solves the problem of large millimeter wave loss and successfully reduces the area. At the same time, this article can contribute to readers’ future optimization and continued research directions, and at the same time contribute simulation and measurement trends to let readers understand the stability of CMOS chip antenna simulation and measurement.

Dual-Band Frequency Selective Surface-Backed Reflectarray for High-Speed Ka-Band Satellites

A dual-band, dual-polarized frequency selective surface (FSS)-backed multilayer reflectarray antenna is designed for 5G high-speed satellites operating at Ka-band uplink and downlink frequencies (20/30 GHz). A reflectarray antenna system consists of two reflectarrays that are separated from each other by an FSS layer that behaves as a planar bandpass filter at Ka-band satellite uplink frequencies. Each reflectarray antenna is designed with dual-polarized unit cells. In order to achieve a uniform phase distribution across the reflectarray surface, physical dimensions and positions of the unit cells with a fixed periodicity are carefully chosen. The FSS conductor is etched to the bottom layer of the 30 GHz reflectarray substrate to save cost and weight. The reflectarray performance is analyzed by using CST Microwave Studio and array theory. A prototype is fabricated, and the results are experimentally verified. The gain of the reflectarray is measured as 21.13 dBi and 26.94 dBi at 20 and 30 GHz, respectively. A crosspol level of more than 35 dB is observed at both frequencies. The simulated and measured results show that the proposed reflectarray is suitable for high-speed Ka-band satellites.

Efficient Improved Local Time Stepping with the Leapfrog Scheme for Transient 3-D Electromagnetic Analyses

An alternate boundary local time stepping (ABLTS) method is proposed for the discontinuous Galerkin time domain method for transient electromagnetic simulations to reduce the computation complexity of the local time stepping (LTS) method. The proposed method exhibites lower storage and time complexity than the conventional LF-LTS method . The stability, accuracy, and effectiveness of the ABLTS method are verified by applying it to the simulation of a resonator cavity and multi-layer microstrip antenna. The numerical results revealed that the developed method is effective for the transient electromagnetic simulation of antennas.

A compact high gain filtering patch antenna for multiband wireless system

A novel compact multilayer patch antenna is designed for triple-band operation with filtering characteristics. The multiband antenna with filtering characteristics is necessary to suppress adjacent band interference. Further, it brings higher out-of-band suppression without deteriorating the in-band gain. This filtering antenna offers size compactness, high gain, and high selectivity with reduced interference. On exciting the antenna, the electromagnetic (EM) coupling takes place from feed to patch through the slotted ground. Then the magnetic field reaches its maximum at the middle of the rectangle patch while the electric field reaches its maximum at the edges. These fields couple with the ‘U’ shaped metallic loops and bring field distribution in it and thus contribute to dual-band resonance at 2.45GHz and 4.15GHz. For better impedance matching, the two ‘U’ shaped metallic loops are employed. The additional middle band at 3.25GHz is attained through the employment of a split rectangular ring around the center patch. The bottom ground is etched with a bent horizontal slot to achieve proper positioning of the lower resonance. The modified CRLH feeding structure is adopted in this antenna to realize radiation null between operating bands. The dimension of the CRLH branches decides the positioning of radiation nulls in the spectrum of interest. This null reduces the interband interference and it is an important feature for any multiband communication system. The usage of via between patch and feed increases the electrical length of an antenna and thus provides size miniaturization. Whereas the position of the via in the patch decides the impedance matching. thus multiple iterations of simulation were done to optimize the via position for better impedance matching. The designed antenna has a compact dimension of 0.21λo × 0.21λo. The realized triple bands have −10dB impedance bandwidth of 180MHz (2.31 to 2.49GHz), 350MHz (3.1 to 3.45GHz), and 850MHz (3.6 to 4.45GHz) with a maximum gain of 5.2dB. Thus the multi-layer antenna not only has proven to be multiband but also incorporated filtering characteristics to lessen interband interferences. The proposed antenna would be beneficial in a multiband wireless system that supports services such as Wifi, WiMAX, and 5G. The antenna is the perfect candidate for the unmanned ariel vehicle (UAV) to be used in emergency and military applications.

A multi-beam circularly polarised Fabry-Perot resonator antenna array using SIW for X-Band applications

ABSTRACT This paper presents a novel multi-layer beamforming antenna array based on Fabry-Perot resonator that is excited by a high-performance compact 4 × 4 Butler matrix using substrate integrated waveguide (SIW) technology for X-band application. The adapted ring patch antenna is fed through the aperture on a rectangular SIW cavity and forms the radiating element in the antenna array. Enhanced characteristics of the antenna array are realised by inserting an electromagnetic bandgap (EBG) structure between the radiating elements and a superstrate constituted from two complementary frequency selective surfaces (FSS) that forms a Fabry-Perot resonator (FPR). Circular polarisation in the proposed FPR SIW antenna array (FPRSAA) is achieved by using a combination of sequential phase rotation and orthogonal feeding techniques. Measured results of antenna array (Ant. II) show |S11| ≤ −10 dB between 8–12.0 GHz, a circular polarisation (CP) gain variation between 15.64–18.54 dBic, 3 dB axial-ratio between 8.5–11 GHz, and scanning angle covering −47 to 47 degrees.

Multiservice Compact Pixelated Stacked Antenna With Different Pixel Shapes for IoT Applications

This paper presents a multi-service pixelated stacked antenna for dual-band application at 5.2 GHz and 5.8 GHz bands. An efficient method for designing multilayer or stacked antennas for multistandard Internet of Things (IoT) applications is proposed in this paper. The proposed antenna topology is based on two different pixel shapes and offers essential aspects such as flexibilities in the design of low-profile single band or multi-band antennas for wireless systems. The antenna design consists of two pixelated layers of radiating patch, consisting of different shaped pixels. The V-shaped binary particle swarm optimization (VBPSO) algorithm has been implemented for the optimization of pixel positions. Only by considering predefined regions, the antenna can be designed and optimized for various design goals. In the design procedure, triangular-shaped pixels are used to form the principal radiating patch, while square-shaped pixels are implemented on the stacked parasitic patch. Measurement and simulation results are in good agreement which proves the accuracy of the design and simulation procedure. The antenna operates at 5.16-5.21 GHz and 5.79-5.86 GHz. With a compact design, the proposed antenna achieves 4.7 dBi and 4.4 dBi gain at 5.2 GHz and 5.8 GHz, respectively. The proposed antenna design methodology offers great potentials to be aligned with specific design requirements of wireless low-profile IoT devices.

Multilayer printed antenna with circular directional pattern and increased directional coefficient

Formulation of the problem. The article explores the possibility of using an array of square open frames to increase the directivity of a multilayer printed antenna with a circular radiation pattern in the azimuthal plane and horizontal polarization. Target. Develop a multi-layer dual-band antenna with increased directivity, emitting/receiving a radio signal in all directions in the azimuthal plane with horizontal polarization. First frequency range: GSM-1800, LTE-1800, UMTS-2100; second frequency band: n79 5G. Results. A new design of a multilayer antenna is proposed, consisting of three printed circuit boards located one above the other. A circular antenna array of F-shaped radiators is placed on the lower dielectric substrate. It is excited by a high-frequency connector. The second board contains arc-curved dipoles located along two circles of different diameters. On the third dielectric substrate there is an array of 45 square open frames. The electrodynamic characteristics of the antenna are calculated and the influence of the array of frames on the directivity coefficient is studied. The antenna operates in two frequency ranges 1.62…2.32 GHz and 4.23…4.95 GHz, the maximum directivity in the first frequency range is 1.9 dB, and in the second 4.6 dB. Practical significance. The antenna can be used as an element of an omnidirectional antenna array of cellular communications of 2-5G generations, to implement the Internet of Things technology, to communicate with moving objects.

Multi-material additive manufacture and microwave-assisted sintering of a metal/ceramic metamaterial antenna structure

Multi-material metal/ceramic 3D structures comprising of metallic silver and ultra-low sintering temperature silver molybdenum oxide ceramics, have been additively manufactured and hybrid densified using microwave-assisted sintering for the first time. Optimum densification conditions at 440 °C / 1 h, resulted in relative permittivity, εr = 10.99 ± 0.04, dielectric losses, tanδ = 0.005 ± 0.001 and microwave quality factor, Q × f = 2597 ± 540 GHz. Applying 2 kW microwave energy at 2.45 GHz for 60 min, was proven sufficient, to densify the metallic Ag infilling electrodes, without causing any macroscopic defects. A fully functional multi-layered antenna structure with a metamaterial artificial magnetic conductor was designed, dual-printed and densified, to showcase the potential of combining multi-material additive manufacturing with microwave-assisted sintering.

On The Resonant Frequency and Bandwidth of Multilayered Square Patch Microstrip Antennas

In the present paper a novel technique has been developed to compute the resonant frequency and bandwidth of electromagnetically coupled multilayered square patch microstrip antenna (MLSPMA) on low (ɛr=2.33) and high (ɛr=10.8 ) index RT Duroid substrate in S and X band of microwave frequencies. The basic antenna structure considered is a multidielectric layered with a spaced parasitic director. The radiator (lower patch) and the parasitic patch (upper patch) are considered to have same and slightly different dimensions, and are perfectly registered (no offset). It is observed that the antenna geometry can be optimised for the required frequency operation and bandwidth by adjusting input parameters and the thickness of the layers.

Investigation and design methods of a compact patch antennas using 3-D MMIC for various applications

This work focused on the design, characterization and investigation of GaAs based multi-layered compact 3D MMIC based antenna. Different patch antennas were designed and characterized along with its S-parameters. Two proposed models of multi-layered patch antenna using V-shaped feeder line and planar feeder line with a spiral transmission line in metal-2 were more compact in size and showed an improvement in performance based on bandwidth compared to the traditional planar feeder line configuration. This implies the proposed planar feed line with the spiral transmission is cost effective. The newly propose planar antenna with a spiral transmission feeder line is 49% more compact in area compared to using the normal planar feeder line. The new design also has wider bandwidth with a bandwidth of 2.99% as compared to the traditional planar with a bandwidth of 1.93%, better input return loss and a slightly lower resonance frequency. Similarly, another multilayer patch antenna was proposed using a V-shaped feeder line, This V-shaped feeder line antenna model showed a much lower resonance frequency (36.50 GHz) compared to normal planar (38.92GHz) and the planar with spiral transmission line model (38.52 GHz).

Design and Analysis of Multi-Layer Patched Efficient Antenna for 28-GHz Applications

Microstrip antennas possess a compact form factor, exhibit a low profile, and demonstrate a lightweight nature, thereby enabling their suitability for deployment on both planar and non-planar surfaces. When the framework is installed, it requires a comparatively small amount of space. The production of printed circuits has become a facile and inexpensive process owing to advancements in contemporary technology. Antennas with a low profile are often required owing to space, weight, cost, performance, simplicity of installation, and aerodynamic profile in powerful planes, spaceships, satellites, and rocket operations. Many other applications, not only mobile radio and wireless communications, have comparable requirements. Microstrip antennas are a useful tool for accomplishing this goal. A proposal has been put forth to utilize a patch antenna for 5G cellular connectivity at 28 GHz, with the aim of generating robust beams on the azimuthal plane. The antenna proposed in this study exhibits a radiation efficiency of 93.46 percent and a total efficiency of 92.80 percent, as demonstrated through simulations. This study showcases the feasibility of producing millimeter-wave antennas operating at 28 GHz through the utilization of cost-effective additive manufacturing techniques. The simulation of all outcomes is conducted through the utilization of the CST Microwave Studio.

Isolation Enhancement of Metamaterial-Inspired Two-Port MIMO Antenna Using Hybrid Techniques

This work utilizes hybrid isolation enhancement techniques to design a highly isolated two-port polarization diversity (PD)-based multiple-input-multiple-output (MIMO) antenna. Initially, an epsilon-negative transmission line-inspired antenna with circular polarization (CP) radiation is designed. Further, the same antenna is converted into a two-element MIMO configuration with an edge-to-edge spacing of 8.35 mm between the antenna elements. Higher antenna isolation is obtained mainly due to two factors. Initially, multiple defected ground structure-based slots are inserted in the antenna ground plane to improve the antenna isolation by 23.5 dB. Secondly, placing an epsilon-and-mu-near-zero-based metasurface superstrate above the two-port MIMO configuration results in bandwidth ranges from 4.768.4.92 GHz and higher isolation of 51 dB. The antenna provides a maximum gain of 6.27 dBi at 4.78 GHz and radiation efficiency better than 85% in the complete working band. Finally, for analyzing the antenna performance in an actual environmental condition, the multilayer MIMO antenna is covered with a Teflon cavity provides a maximum dimension of 0.84 λ0× 0.38 λ0 ×0.16 λ0 at 4.8 GHz. Furthermore, the MIMO antenna port-1 provides right-handed CP radiation, while port-2 provides left-handed CP radiation, confirming the PD performance.

Multi-Layer Beam Scanning Leaky Wave Antenna for Remote Vital Signs Detection at 60 GHz.

A multi-layer beam-scanning leaky wave antenna (LWA) for remote vital sign monitoring (RVSM) at 60 GHz using a single-tone continuous-wave (CW) Doppler radar has been developed in a typical dynamic environment. The antenna's components are: a partially reflecting surface (PRS), high-impedance surfaces (HISs), and a plain dielectric slab. A dipole antenna works as a source together with these elements to produce a gain of 24 dBi, a frequency beam scanning range of 30°, and precise remote vital sign monitoring (RVSM) up to 4 m across the operating frequency range (58-66 GHz). The antenna requirements for the DR are summarised in a typical dynamic scenario where a patient is to have continuous monitoring remotely, while sleeping. During the continuous health monitoring process, the patient has the freedom to move up to one meter away from the fixed sensor position.The proposed multi-layer LWA system was placed at a distance of 2 m and 4 m from the test subject to confirm the suitability of the developed antenna for dynamic RVSM applications. A proper setting of the operating frequency range (58 to 66 GHz) enabled the detection of both heart beats and respiration rates of the subject within a 30° angular range.

GA based optimized graphene antenna design for detection of explosives and drugs using THz spectroscopy

Explosives and contraband drug detection have been a persistent problem for the last few decades and have emerged as one of the numerous crucial issues in public safety and counter-terrorism. Due to the risks to human cells and the inability to detect all forms of explosive materials, traditional detection techniques like x-rays and metal detectors are inadequate to combat these issues. Terahertz imaging and spectroscopy have solved the aforementioned problems because nonionizing radiation is harmless to humans and can also find objects hidden under non-metals. The proposed research work designed multi-layered dual-band graphene antennas for the THz spectroscopy applications utilising uni-layer triple substrate method, i.e., three substrates at the same height w.r.t. ground. The genetic algorithm optimizes a design antenna with 5.59 & 7.71 THz resonant frequencies, lower used to detect TNT explosives and upper ones used to detect melatonin drugs. The optimized antenna has radiation efficiency (%) values of 79.51 & 77.51, S11 parameters of −48.22 & −43.95, VSWR of 1.007 & 1.012 and bandwidths of 145.9 & 148.4 GHz at both resonating frequencies. In terms of antenna's gain (dB) and directivity (dBi), the optimized antennas show better performance with values of 4.65 & 2.97 and 5.87 & 4.07, respectively. The overall results demonstrated that, while being smaller, the optimized antenna outperforms the conventional one.